1. Field of the Invention
This invention relates to closed loop, programmable power and communication system for buildings, and particularly for use in residential dwellings. The closed loop programmable power concept relies on two way communication between a central power developing system and power operated devices, such as domestic appliances, connected to the system. More particularly, the invention relates to a system wherein the communication link is integrated with the power cable, the communication link being an optical fiber.
2. Description of the Prior Art
The concept of closed loop programmable power is a spin off of research work in the United States directed to the development of a home of the future that combines the centralized microprocessor controls of building systems and household appliances with the unified distribution of power and communications. According to the National Electrical Code of the United States, closed loop and programmed power is defined as a premise power distribution system jointly controlled by a signalling between the energy controlling equipment and the utilization equipment. This concept may be applied to a residential environment by having power outlets and associated branch circuits maintained in a de-energized state unless called upon to feed an appliance connected to the home's power distribution network. The appliance would have to identify itself and communicate its power requirements and operational parameters to a power system controller in order to qualify for the receipt of power. These requirements would be unique to a particular appliance and would be encoded on a micro chip built into the appliance. Any irregularities sensed by the controller would consequently prevent the device from receiving power. On the basis of closed loop power distribution, the appliance would be expected to communicate its power requirements as well as unique operational parameters to the control system and this communication would continue during operation. Any deviation from the specified requirements would be communicated immediately to the controller and if the deviations indicated a malfunction, power would be removed from the appliance. Malfunctions such as excess current requirements, signalling defective equipment or short circuit in the equipment itself or the power cable leading to the equipment would be reported to the power controller and power removed from the circuit. Similarly, objects accidentally or intentionally placed in an outlet would not communicate power requirements to the power controller and the outlet would remain de-energized. Electrocution, which is a major home safety problem, would be significantly reduced. The occurrence of electrically generated house fires caused by short circuited wiring would also be reduced.
According to the proposed system, a residence would be provided from an external source with the normal power supplied by the utility service, and a power panel in the residence has an output with a range of voltage and line frequency capabilities, e.g. 60 Hz 120 volts: 60 Hz 220 volts: 400 cycle 120 volts and 48 volt DC. Hence, a range of appliances having different voltage and line frequency requirements could be coupled to a standard power socket. This would lead to the development of a range of appliances using 48 volt DC motors for appliances such as washing machines, dryers, electric drills, etc. The utilization of DC motors would eliminate the requirement for expensive belt or gear drive arrangements.
It is further contemplated that the proposed loop system would provide in an integrated system, access to external communications networks such as telephone, cable television, FM broadcast, as well as remote monitoring facilities. Under the proposed systems, the power outlets in the residence would include sockets for receiving operating power as well as an arrangement of sockets adapted to provide the communication link between an appliance to be plugged therein and the central power controller. The central power controller which will connect the external power source to the residence will be controlled by an interface which will receive communications information from the appliance plugged into the socket. The interface will interrogate the appliance, assess power requirements, instruct the power controller to deliver the required output, and to continually monitor operation of the appliance. In the proposed system, the communication link comprises a plurality of copper conductors integrated with the power cable or connected in parallel thereto.
A central distribution panel will, in addition to receiving external power, also receive external communication inputs which will be distributed to local interface networks within the residence. Certain appliances will be dedicated such as dryers and stoves and these appliances will be connected directly to the central distribution system. Other lower power requirement appliances such as televisions, radios, etc. will share power from the localized interface networks. It will be apparent to one skilled in the art that the use of copper as a communication link has some limitations. For example, EMI/RFI interference, unless elaborate shielding techniques were employed, would adversely effect the quality of audio and video signals. Considering the large number of potential communication links, a large number of copper wires, up to 25, could be required. In view of the specialized communication interconnections, a specialized plug and socket system and the associated hardware and outlet boxes would be required.